text: (function() {
  
      // detect if IE : from http://stackoverflow.com/a/16657946
      var ie = (function(){
          var undef,rv = -1; // Return value assumes failure.
          var ua = window.navigator.userAgent;
          var msie = ua.indexOf('MSIE ');
          var trident = ua.indexOf('Trident/');
  
          if (msie > 0) {
              // IE 10 or older => return version number
              rv = parseInt(ua.substring(msie + 5, ua.indexOf('.', msie)), 10);
          } else if (trident > 0) {
              // IE 11 (or newer) => return version number
              var rvNum = ua.indexOf('rv:');
              rv = parseInt(ua.substring(rvNum + 3, ua.indexOf('.', rvNum)), 10);
          }
  
          return ((rv > -1) ? rv : undef);
      }());
  
  
      // disable/enable scroll (mousewheel and keys) from http://stackoverflow.com/a/4770179
      // left: 37, up: 38, right: 39, down: 40,
      // spacebar: 32, pageup: 33, pagedown: 34, end: 35, home: 36
      var keys = [32, 37, 38, 39, 40], wheelIter = 0;
  
      var height = (window.innerHeight > 0) ? window.innerHeight : screen.height;
  
      function preventDefault(e) {
          e = e || window.event;
          if (e.preventDefault)
              e.preventDefault();
          e.returnValue = false;
      }
  
      function keydown(e) {
          for (var i = keys.length; i--;) {
              if (e.keyCode === keys[i]) {
                  preventDefault(e);
                  return;
              }
          }
      }
  
      function touchmove(e) {
          preventDefault(e);
      }
  
      function wheel(e) {
          // for IE
          //if( ie ) {
          //preventDefault(e);
          //}
      }
  
      function disable_scroll() {
          var width = (window.innerWidth > 0) ? window.innerWidth : screen.width;
          if(width > 768){
              window.onmousewheel = document.onmousewheel = wheel;
              document.onkeydown = keydown;
              document.body.ontouchmove = touchmove;
          }
      }
  
      function enable_scroll() {
          window.onmousewheel = document.onmousewheel = document.onkeydown = document.body.ontouchmove = null;
      }
  
      var docElem = window.document.documentElement,
          scrollVal,
          isRevealed,
          noscroll,
          isAnimating,
          container = document.getElementById( 'wrapper' ),
          trigger = container.querySelector( 'button.trigger' );
  
      function scrollY() {
          return window.pageYOffset || docElem.scrollTop;
      }
  
      function scrollPage() {
          scrollVal = scrollY();
  
          if( noscroll && !ie ) {
              if( scrollVal < 0 ) return false;
              // keep it that way
              window.scrollTo( 0, 0 );
          }
  
          if( classie.has( container, 'notrans' ) ) {
              classie.remove( container, 'notrans' );
              return false;
          }
  
          if( isAnimating ) {
              return false;
          }
  
          if( scrollVal <= 0 && isRevealed ) {
              toggle(0);
          }
          else if( scrollVal > 0 && !isRevealed ){
              toggle(1);
          }
      }
  
      function toggle( reveal ) {
          isAnimating = true;
  
          if( reveal ) {
              classie.add( container, 'modify' );
          }
          else {
              jQuery(".topImage").removeClass("fix-zindex");
              noscroll = true;
              disable_scroll();
              classie.remove( container, 'modify' );
          }
  
          // simulating the end of the transition:
          setTimeout( function() {
              isRevealed = !isRevealed;
              isAnimating = false;
              if( reveal ) {
                  noscroll = false;
                  enable_scroll();
                  jQuery(".topImage").addClass("fix-zindex");
                  window.scrollTo( 0, 1);
              }
          }, 700 );
      }
  
      // refreshing the page...
      var pageScroll = scrollY();
      noscroll = pageScroll === 0;
  
      disable_scroll();
  
      if( pageScroll ) {
          isRevealed = true;
          classie.add( container, 'notrans' );
          classie.add( container, 'modify' );
      }
  
      window.addEventListener( 'scroll', scrollPage );
      trigger.addEventListener( 'click', function() { toggle( 'reveal' ); } );
  
      $('.topImage').css('height', height);
  
  })();